The present invention relates to a zinc alloy electroplating bath and the process of electroplating a zinc alloy onto a conductive substrate using the bath. More particularly, the present invention relates to improved compositions and processes for the electro-deposition of zinc alloy from zinc alloy plating baths comprising a water soluble derivative of .beta.-amino-propionic acid.
Electro-deposited zinc alloy of a semi-bright to a lustrous appearance is desirable to provide a decorative plating appearance while simultaneously imparting excellent corrosion protection. Generally speaking, zinc alloys can be deposited on a conductive substrate by means of a zinc alloy electroplating bath; such as a zinc-nickel, zinc-cobalt, or zinc-nickel-cobalt bath. Zinc alloy plating baths and processes are employed to provide zinc alloy deposits on a variety of substrates and are often used in conjunction with ferrous substrates such as iron or steel.
The zinc alloy plating bath and process of the present invention involves use of a brightening additive which can be used in a wide variety of types of zinc alloy plating baths over broad pH and current density ranges to provide a semi-bright to bright zinc alloy deposit having excellent ductility characteristics. The zinc alloy plating bath of the present invention is commercially useful and is characterized, in part, by its flexibility and versatility in use to obtain excellent zinc alloy plating results.
A further understanding of the present invention will be obtained from the following description and examples thereof. Unless otherwise indicated, in the following description and examples, all parts and percents are by weight and all temperatures are in degrees Farenheit.